Tamoxifen is a selective estrogen receptor modulator, meaning that it targets estrogen in the breast independent of ovarian production of
estrogen. However, if you have had your ovaries removed, then you would be postmenopausal
and could possibly take an aromatase inhibitor instead of tamoxifen. Either way, if your breast cancer is hormone receptor positive, then hormone therapy would likely be recommended as the body does produce estrogen outside of the ovaries.